All tracknumber fields in pushqueue are 0

I don’t know whether this is a bug or by design - when I receive a pushQueue event over websockets, all the tracknumber fields in the queue show 0. Isn’t tracknumber supposed to be the position of the track within the queue, or does it have a different use?

[“pushQueue”,[{“uri”:“mnt/NAS/Albums/Francesco De Gregori/Francesco De Gregori/07 - Chissa dove sei.flac”,“service”:“mpd”,“name”:“7 - Chiss\xc3\xa0 dove sei”,“artist”:“Francesco De Gregori”,“album”:“Francesco De Gregori”,“type”:“track”,“tracknumber”:0,“albumart”:"/albumart?cacheid=207&path=%2FNAS%2FAlbums%2FFrancesco%20De%20Gregori%2FFrancesco%20De%20Gregori&metadata=false",“duration”:94,“samplerate”:“44.1 KHz”,“bitdepth”:“16 bit”,“trackType”:“flac”,“channels”:2},{“uri”:“mnt/NAS/Albums/Francesco De Gregori/Francesco De Gregori/08 - A lupo.flac”,“service”:“mpd”,“name”:“8 - A lupo”,“artist”:“Francesco De Gregori”,“album”:“Francesco De Gregori”,“type”:“track”,“tracknumber”:0,“albumart”:"/albumart?cacheid=207&path=%2FNAS%2FAlbums%2FFrancesco%20De%20Gregori%2FFrancesco%20De%20Gregori&metadata=false",“duration”:205,“samplerate”:“44.1 KHz”,“bitdepth”:“16 bit”,“trackType”:“flac”,“channels”:2},{“uri”:“mnt/NAS/Albums/Francesco De Gregori/Rimmel/01 - Rimmel.flac”,“service”:“mpd”,“name”:“1 - Rimmel”,“artist”:"Francesco De …